Work is proposed in three areas: 1) To continue the physico-chemical investigations of ribosomes and polynucleotides, with a view to understanding cation binding and other electrostatic effects on the reactions of initiation of protein synthesis. In particular, to determine experimentally the relative contribution of specific site binding to the total interaction of Mg2+ and other Mn+ with the polyanionic backbone of polynucleotides, principally by 23Na, 39K, 25Mg and 31P NMR. To investigate counterion, coion, and polyelectrolyte interactions by Grand Canonical Monte Carlo calculations, which are intrinsically more capable of systematic extension and of specialization to real ions and structure than either "condensation" or "Poisson-Boltzmann" calculations. 2) To determine the free concentrations of dominant cations (K+, Na+, NH4+, Mg2+, putrescine and spermidine) in exponentially growing E. coli, in order to determine the range of correlated sets of ionic conditions in which ribosome function is outwardly expressed. 3) With high priority to continue investigating the mechanism of initiation of protein synthesis (obligate vs. unnecessary dissociation of ribosomes and subunits, the true role of IF3, particularly of other species), with specific emphasis on the role of thermorubin to dissect the reaction sequence, using standard filter binding, as well as fluorescence depolarization, stopped-flow and pressure-jump studies.